Apparatus for producing dust



Dec. 14, 1965 c. D. JACOBS 3,223,335

APPARATUS FOR PRODUCING DUST Filed Sept. 20, 1962 3 Sheets-Sheet 1 COLLECTOR SUCTION FAN 47 8/ 5/ &/ was hl ul INVENTOR Che/lea flJa cabs ATTORNEYS Dec. 14, 1965 c. D. JACOBS APPARATUS FOR PRODUCING DUST 3 Sheets-Sheet 2 Filed Sept. 20, 1962 ATTORN E Y5 United States Patent 3,223,335 APPARATUS FOR PRQDUCING DUST Charles D. Jacobs, 1100 S. Lakeside Drive, Lake Worth, Fla. Filed Sept. 20, 1962, Ser. No. 225,097 8 Claims. (Cl. 241-109) This invention relates to a dust producer and more particularly to a new and improved wheeled device for producing very fine particles of dust from dry, granular pulverant material, such as sand or the like.

In the past, devices for producing fine dust particles of a size smaller than 200 mesh, from dry sand or other dry, granular, pulverant material, have been rather complicated in structure, expensive to manufacture and maintain, as well as being difficult to operate properly.

It is, therefore, an object of the present invention to provide a device adapted to produce fine particles of dust from pulverant material, which is simple in structure, economical to manufacture and maintain, and which is very easy to operate.

Another object of the present invention is to provide a wheeled device adapted to ride on the surface of a layer of dry, coarse pulverant material to produce fine dust particles therefrom.

Another object is to provide a control system adapted to automatically maintain a layer of dry pulverant material of the proper depth beneath the wheels of a revolving wheeled device for producing fine particles of dust from the pulverant material.

Another object is to provide a fluid conveying system adapted to control the size of the dust particles removed from the housing of a revolving wheeled dust producer.

These and other objects of the invention will become more apparent from the following specification and claims when taken in conjunction with the drawings, in which:

FIG. 1 is a side elevational view of the device;

FIG. 2 is a horizontal, sectional view taken on line 2-2 of FIG. 1;

FIG. 3 is an enlarged, vertical, sectional view of the device taken on line 33 of FIG. 2;

FIG. 4 is an enlarged, fragmentary, sectional view taken on line 4-4 of FIG. 3;

FIG. 5 is an enlarged, fragmentary, sectional view taken on line 5-5 of FIG. 3; and

FIG. 6 is an enlarged, fragmentary, elevational view taken on line 66 of FIG. 3.

The dust producer of the present invention includes a closed housing 1 having a lower, vertically disposed, cylindrical body 3 mounted on a circular concrete base 5. A ring 7 formed of angle iron fits tightly around the periphery of cylindrical body portion 3 at the lower edge thereof and is attached to body 3 as by weld 9.

The upper edge of body 3 is reinforced by a ring 11, formed of angle iron which is fixedly secured around the periphery of body 3 at the upper edge thereof as by weld 13. One wall 14 of ring 11 extends radially outwardly to form a support for a conically shaped cover 15. The lower edge of cover 15 is provided with a radially extending fiange 17, which is seated on support wall 14 of ring 11 and removably attached thereto by threaded bolts 19 passing through suitably aligned openings in flange 17 and in Wall 11. Lateral movement or shifting of cylindrical body 3 on concrete base 5 may be prevented as by inserting three posts 21 into three equally spaced openings 23 formed in concrete base 5 at the outer periphery of angle iron ring 7. The upper end of cover 15 is truncated and provides an opening 25 in which is mounted, for vertical sliding movement, a tube 27 for supplying dry, pulverant material to the interior of housing 1. The upper end of tube 27 is formed with a funnel-shaped inlet opening 28 to receive the pulverant material from any suitable source of supply. The lower end of the tube is reinforced by an angle iron ring 29 fitting tightly around the tube and secured thereto by weld 31.

A series of vehicle wheels 33, rotatably mounted on a heavy metal ring 35, provide a circular, wheeled carriage 36 adapted to revolve in housing 1 and to ride on the surface of a layer of dry, granular, pulverant material S, which is to be reduced to fine particles of dust. The outer diameter of ring 35 is slightly smaller than the inner diameter of cylindrical body 3 to provide clearance between the periphery of the ring and the inner wall of the body. Wheels 33, which are provided with rubber tires 37, are rigidly attached to the inner periphery of ring 35 by conventional vehicle steering wheel spindles 39. As is customary in the construction of such a spindle, the antifriction bearings, not shown, are protected from dust and other foreign matter by a hub cap 41 attached to the wheel 33 at the outer end of the spindle 39 and by a felt seal, not shown, positioned between the wheel and spindle at the inner end of the spindle. The plate 42, which is formed on the inner end of conventional steering wheel spindles 39, is attached to the inner periphery of ring 35 by bolts 43 passing through suitable elongated openings 44 formed in the plate and into threaded openings formed in ring 35. The camber of the wheels as well as the toe-in may be adjusted to the most suitable angle of contact with the pulverant material by inserting shims between plates 42 and ring 35 prior to tightening bolts 45. In order to compensate for tire Wear or tires or wheels of ditferent size and to insure that each wheel bears equally on the material to be pulverized, wheels 33 may be vertically adjusted on ring 35 by means of elongated openings 44 before tightening bolts 43.

Four equally spaced, rectangular-shaped openings 45 are formed in the wall of cylindrical body 3 to provide for admitting air to the interior of housing and for inserting therethrough means to drive carriage 36. Rectangular frames 47, formed of angle iron, are attached by welds 43 to the outer Wall of cylindrical body 3 around openings 45 to reinforce the body in the area of the openings.

Carriage 36 is frictionally driven by four horizontally disposed vehicle wheels 51, having rubber tires 53 mounted thereon. Drive wheels 51 are rotatably mounted on conventional, tapered, vehicle steering wheel spindles 55, with a portion of the outer periphery of tires 53 extending through rectangular openings 45 and into frictional contact with the outer periphery of ring 35 of carriage 36. A rectangular-shaped bearing block 57, welded as at 59 to the plate 60 formed at the inner end of spindle 55, is slidably mounted radially of ring 35 in a T-shaped guideway 61 formed in a metal support plate 63. The plates 63 are attached to the upper surface of platforms 65, which extend upwardly from the upper surface of base 5 adjacent opening 45, by threaded bolts 67 extending through openings 69 formed in plate 63 and into threaded lag shields 71 inserted in openings 73 provided in platforms 65.

The wheels 51 are adapted to be frictionally rotated and at the same time to be urged into frictional contact with ring 35 by pulleys 75 which are keyed or otherwise fixedly secured to the upwardly extending motor shafts 77 of vertically disposed, adjust-ably mounted electric motors 79. The threaded nuts 81, mounted on the outer end of motor shafts 77, secure pulleys 75 onto the motor shafts. Each electric motor 75 is independently, adjustably mounted on base adjacent one of the wheels 51 for movement in radial alignment with the corresponding wheel. A recessed frame 83, having a generally T-shaped bearing block 85 secured to the lower surface thereof by weld 87, fits closely about the lower bell 89 of each motor 79 and is attached thereto by threaded bolts 91 passing through suitable openings 93 formed in the wall of frame 83 and into threaded openings provided in the bell 89 of the motor. A metal plate 95, secured to base 5 by bolts 97, is provided with a generally T-shaped guideway 99 slidably mounting therein bearing block 85.

A threaded opening 101 formed in each bearing block 85 extends horizontally therethrough and receives the inner end of a threaded mating screw 103 for adjusting block 85 in guideway 99. An unthreaded portion 102 of screw 103, adjacent the outer end thereof, is rotatably mounted in a thrust bearing opening 104, formed in a vertical wall 105. Bolts 106 secure wall 105 to the outer end of plate 95. The screws 103 which are adapted to be rotated by a handle or crank 107, are suitably supported in bearing openings 104 against axial movement upon rotation of the screws. A locknut 109 is threaded onto each screw 103 between plate 95 and wall 105 and is adapted to be jammed against the face of bearing block 85 to prevent rotation of screw 103 when motor 75 is in the desired adjusted position.

It will be seen that each motor 79 with pulley 75 may be moved radially inwardly by turning screw 103. As pulley 75 pushes against the periphery of tire 53, wheel 51 will slide radially inwardly in guideway 61 until tire 53 frictionally engages ring 35. By properly adjusting the position of each of the pulleys 75, tires 53 will center ring 35 within body 3 in spaced relation to the inner wall thereof.

The pulverant material S, when furnished through tube 27, is deposited in a pile at the center of housing 1 and assumes a cone-shaped configuration. A circular recess 122, formed in the upper surface of base 5, terminates a short distance outwardly beyond tires 37 and serves to retain a layer of the pulverant material beneath the tires 37. By adjusting feed tube 27 vertically in opening 25, a layer of the pulverant material of the desired depth will be deposited in recess 122 at the outer periphery of the pile beneath tires 37. A winch 123, connected to the tube 27 by a pair of cables 125, is adapted to automatically raise or lower tube 27 to maintain the layer of pulverant material beneath tires 37 at a predetermined depth. Cables 125, which are attached at one end thereof to brackets 127 rigidly secured to opposite sides of tube 27, pass over pulleys 129 and are attached at the other end thereof to the rotary drum 130 of winch 123.

The current required for operating motors 9 to drive carriage 36 at a given speed on a layer of pulverant material of a predetermined depth, is substantially constant. Means for automatically controlling the depth of the layer of pulverant material beneath tires 37 is schematically shown and includes a reversible electric motor 131, operably connected to the drum 130 of winch 123 to rotate the drum in either direction. Motor 131 is adapted to be actuated by an electrical sensing device 133 of any suitable type attached to a wire 135 furnishing current to one of the motors 79. Sensing device 133 is adapted to detect any increase or decrease from the normal amount of current required by motor 79 to drive carriage 36 at a given speed on a layer of pulverant material of a predetermined depth and to transmit an electric signal through wires 137 to actuate motor 131 in response to any such increase or decrease in the amount of current required. A decrease in the current passing through wire to operate motor 79 will indicate a decrease in the depth of the layer of pulverant material beneath tires 37 and will result in winch motor 131 being actuated to raise tube 27 to increase the depth of the layer of pulverant material. On the other hand, an increase in the current passing through wire 135 will indicate an increase in the depth of the layer of pulverant material and will result in motor 131 being actuated to lower tube 27 to decrease or stop the flow of pulverant material being discharged from the tube.

When carriage 36 is driven on a layer of dry, pulverant material S, a scufling or rubbing action, as well as a crushing action, takes place between the pulverant material and the tires 37 causing the pulverant material to be reduced to a fine, powdery dust. As carriage 36 is unconfined vertically, it is free to accommodate itself to any unevenness or variations in the depth of the layer of pulverant material. Vertical movement of carriage 36 is limited only by the width of ring 35 which must maintain frictional contact with tires 53 of wheels 51.

Carriage 36 may be revolved in housing 1 at a speed of approximately 200 rpm. The turbulence imparted to the air in housing 1 by carriage 36 causes the dust which has been produced to become air-borne. The dustladen air is adapted to 'be withdrawn from housing 1 through an opening 139 formed in cover 15 and through conduit 141 extending between opening 139 and the inlet of a suction fan 143. Suitable couplings 145 may be employed to secure the sections of conduit 141 together. The discharge of suction fan 143 is connected by a conduit 147 to any suitable collector or dust separator, not shown. Suction fan 143 may be of the squirrel-cage type adapted to be driven by a variable speed, electric motor 149.

The air inlet openings 45 in body 3 are partially obstructed by tires 53 and are of such a size as to restrict the flow of air therethrough to maintain a partial vacuum in housing 1 and thus prevent the escape of dust-laden air to the surrounding atmosphere. A supply of pulverant material S is maintained in tube 27 during operation of the device to prevent air from entering housing 1 therethrough.

The size of the particles of dust entrained in the air being withdrawn from housing 1 is controlled by regulatmg the speed of motor 149, which is connected to suction fan 143. The slower suction fan 143 is rotated, the finer Will be the dust particles entrained and conversely, the faster suction fan 14-3 is rotated, the coarser will be the particles entrained.

Access to the interior of housing 1 may be obtained lay disconnecting couplings 145, removing bolts 19 and lifting cover 15 from body 3. The entire housing 1 may be raised from the surface of base 5 by high lift screw acks 151 positioned beneath three angle brackets 153, which are spaced 120 degrees apart and welded to the outer surface of body 1.

It will be obvious to one skilled in the art that certain modifications and alterations in the structure and method of operation disclosed herein may be made without departing from the spirit of the invention. For example, while eight wheels 33 are shown attached to ring 35, and four wheels 51 are shown for rotating carriage 36, it would be obvious that a fewer or greater number could be employed. Further, additional means, such as guide rollers, could be employed to center carriage 36 within housing 1, in which case any desired number of wheels could be employed to frictionally drive the carriage.

The invention is not to be limited to the preferred form of the invention which is disclosed for the purpose of illustration, but is intended to encompass such changes, modifications, and substitution of equivalents which would occur to those skilled in the art as fall within the scope of the appended claims.

I claim:

1. Apparatus for producing fine particles from granular, pulverant material, comprising: a substantially closed housing having at least three equally spaced openings formed in the side walls thereof; a circular wheeled carriage rotatably mounted in said housing adapted to ride on the surface of a layer of said pulverant material disposed on the floor of said housing for reducing the particle size of said pulverant material; a series of at least three, horizontally disposed drive wheels rotatably mounted on vertical axes extending through said openings and into frictional contact with said carriage; and means for rotating said drive wheels.

2. Apparatus for producing fine particles from granular, pulverant material, comprising: a substantially closed housing; a circular, wheeled carriage rotatably mounted in said housing and adapted to ride on the surface of said pulverant material, said wheeled carriage including: a horizontally disposed, heavy metal ring; and a series of at least three equally spaced, vertically disposed wheels rotatably mounted on said ring supporting said ring for rotation, said carriage being unconfined for limited vertical movement; and means for rotating said carriage to reduce the particle size of said pulverant material.

3. Apparatus for producing fine particles from granular, pulverant material, comprising: a substantially closed cylindrical housing having at least three equally spaced openings formed in the side wall thereof; a carriage including a circular ring having at least three equally spaced, vertically disposed wheels rotatably mounted on the inner periphery thereof supporting said ring for rotation on the surface of a layer of said pulverant material disposed on the floor of said housing to reduce the particle size thereof, said carriage being unconfined for limited vertical movement; a horizontally disposed drive wheel rotatably mounted on a vertical axis extending through each of said openings in said housing wall and into frictional contact with the outer periphery of said ring; and means for rotating said drive wheels.

4. Apparatus defined in claim 3 including a circular recess formed in the upper surface of said floor beneath said vertically disposed wheels, said layer of pulverant material being disposed in said recess and confined therein against lateral movement.

5. Apparatus for reducing granular, pulverant material to fine particles, comprising: a substantially closed housing having a supply opening formed in the cover thereof; a wheeled carriage rotatably mounted in said housing about a vertical axis co-axial with the axis of said opening in said cover and adapted to ride on the surface of a layer of said pulverant material disposed on the floor of said housing; a vertically disposed supply tube slidably mounted for vertical movement in said supply opening for conveying said pulverant material into said housing; means for raising and lowering said tube to control the flow of said pulverant material into said housing and thereby the depth of said layer of said pulverant material beneath the wheels of said carriage; and means for rotating said carriage on said layer of said pulverant material to reduce the particle size thereof.

6. Apparatus for reducing granular pulverant material to fine particles, comprising: a substantially closed housing having a supply opening formed in the cover thereof; a wheeled carriage rotatably mounted in said housing about a vertical axis coaxial with the axis of said opening in said cover adapted to ride on the surface of a layer of said pulverant material disposed on the floor of said housing; a vertically disposed supply tube slidably mounted for vertical movement in said supply opening for conveying said pulverant material into said housing; means for raising and lowering said tube to control the flow of said pulverant material into said housing and thereby the depth of said layer of said pulverant material beneath the wheels of said carriage; means for sensing the power required to rotate said carriage on a layer of said pulverant material of a predetermined depth; means controlled by said sensing means in response to an increase or decrease in said power from that required to rotate said carriage on a layer of said pulverant material of predetermined depth adapted to actuate said means for raising or lowering said supply tube to maintain at a predetermined depth said layer of pulverant material; and means for rotating said carriage on said layer of said pulverant material to reduce the particle size thereof.

7. Apparatus for producing fine particles of dust from dry, granular, pulverant material, comprising: a substantially closed cylindrical housing having a cylindricallyshaped body portion formed with at least three equally spaced openings in the side Wall thereof and an opening formed in the cover thereof; a horizontally disposed, heavy metal ring in said housing supported in spaced relation to the walls of said housing; a series of at least three equally spaced, vertically disposed wheels, having rubber tires mounted thereon, rotatably mounted on the inner periphery of said ring, supporting said ring for rotation on the surface of a layer of dry, pulverant material disposed on the floor of said housing to reduce said pulverant material to dust; a circular recess formed in the upper surface of said floor beneath said vertically disposed wheels confining said layer of pulverant material against lateral movement; a horizontally disposed, rotatably mounted drive wheel supported outside of said housing and immediately adjacent each of said openings for sliding movement radially of said ring, said drive wheels extending through said openings formed in the side wall of said housing and frictionally engaging the outer periphery of said ring; rotatably mounted pulley means adjustably mounted for movement radially of said ring, frictionally engaging the periphery of said horizontally disposed wheels and moving said horizontally disposed wheels into frictional engagement with said ring; means for adjusting said pulley means radially of said ring; electric motor means for rotating said pulley means; a vertically disposed tube, slidably mounted for vertical movement in said opening formed in said cover of said housing for conveying said pulverant material into said hous ing; said tube being disposed axially of .said ring; suction means communicating with said housing adapted to draw air into said housing through said openings in said side walls thereof and to withdraw said air with entrained dust particles from said housing; means to vary the degree of said suction for controlling the rate of air fiow through said housing and the size of the dust particles entrained thereby; means for raising and lowering said tube to control the flow of said pulverant material into said housing and thereby the depth of said layer of pulverant material beneath said vertically disposed wheels; and means for sensing the amount of current furnished to said electric motor means; said sensing means being responsive to variations from the amount of said current normally furnished to said electric motor means to actuate said means for raising and lowering said tube.

8. Apparatus for producing fine particles from granular, pulverant material, comprising: a substantially closed cylindrical housing having at least three equally spaced openings formed in the side wall thereof; a carriage including a circular ring having at least three equally spaced, vertically disposed wheels rotatably mounted on the inner periphery thereof supporting said ring for rotation on the surface of a layer of said pulverant material disposed on the floor of said housing to reduce the particle size thereof, said carriage being unconfined for limited vertical movement; and means for driving said carriage including a horizontally disposed, rotatably mounted, drive wheel supported outside of said housing and immediately adjacent each of said openings for sliding movement radially of said ring, said drive wheels extending through said openings in said housing and into frictional contact with the periphery of said ring; rotatably mounted pulley means adjustably mounted for movement radially of said ring fn'ctionally engaging the periphery of said horizontally disposed wheels and urging said horizontally disposed wheels into frictional engagement with said ring; means for adjusting said pulley means radially of said ring; and means for rotating said pulley means.

References Cited by the Examiner 8 Lane 241109 X Jesson et al 241-109 X Simpson 24158 X Bruchsaler 241-109 X McIlvaine 241107 ROBERT C. RIORDON, Primary Examiner.

I. SPENCER OVERHOLSER, Examiner. 

1. APPARATUS FOR PRODUCING FINE PARTICLES FROM GRANULAR, PULVERANT MATERIAL, COMPRISING: A SUBSTANTIALLY CLOSED HOUSING HAVING AT LEAST THREE EQUALLY SPACED OPENINGS FORMED IN THE SIDE WALLS THEREOF; A CIRCULAR WHEELED CARRIAGE ROTATABLY MOUNTED IN SAID HOUSING ADAPTED TO RIDE ON THE SURFACE OF A LAYER OF SAID PULVERANT MATERIAL DISPOSED ON THE FLOOR OF SAID HOUSING FOR REDUCING THE PARTICLE OF SAID PULVERANT MATERIAL; A SERIES OF AT LEAST THREE, HORIZONTALLY DISPOSED DRIVE WHEELS ROTATABLY MOUNTED ON VERTICAL AXES EXTENDING THROUGH SAID OPENINGS AND INTO FRICTIONAL CONTACT WITH SAID CARRIAGE; AND MEANS FOR ROTATING SAID DRIVE WHEELS. 